It has been medically established that the great majority of malignant mammary tumors act as localized heat sources. The temperature of a breast affected by a malignant tumor remains elevated, while a normal breast fluctuates through a 24 hour temperature cycle. The normal 24 hour temperature cycle comprises a relatively lower temperature during the day and higher temperature at night. The temperature difference between the normal breast and that of a breast containing a malignant tumor provides the basis for the diagnosis of breast cancer by thermographic techniques now in widespread use. The physiological basis is that the malignant process results in a local temperature increase which warms the skin over the general region of the tumor. The present thermography involves the photographing of the breast by means of infrared techniques. The only infrared source is the body heat itself, the higher temperature of the malignancy appearing on the thermograph. While thermography is an effective means for the early diagnosis of breast cancer it is not particularly practical for mass screening of a normal population. A high skilled radiologist is required to analyze the thermograph. In addition, the equipment is expensive and a considerable amount of skilled technician time is required. Furthermore the prospective candidate for diagnosis must be sufficiently motivated to initiate contact with the physician. There is a normal reluctance to do so by those individuals who have no symptoms or who harbor a fear of visiting a physician.
The present invention, while based on the same physiological processes as thermography, is much more suitable for mass screening of the populace. The present invention comprises a temperature-responsive device retained in thermal contact with each breast by means of a brassiere. The brassiere also contains a temperature difference integrator circuit, whereby the difference in mean temperature between the two breasts may be integrated over a period of time. The device is worn for a period of several days in the normal manner, and the integrated temperature difference is then read by a technician. The transaction may be carried out by mail to a central location as will be apparent. Physician time is not required in evaluation of test results. The device readouts may be performed by technicians, and the subject may be contacted by correspondence. Further the cost is apparently low since the brassiere may be reused many times. Only the battery must be replaced regularly. Since the prospective candidate for mass screening need not necessarily visit a physician or any type of medical center to complete the entire test and learn the results, that segment of the population which hesitates to visit a physician can be covered.
It is therefore the object of this invention to provide a method and apparatus for mass screening of the populace for breast malignancies.